Joint and method of making same



v iMa rch 21, 1-939. I 'JENSEN 2,151,032

JOINT AND METHOD OF MAKING SAME Filed June '2 l, 1937 Y 0)? ewe/2' I oh'TolQisyf 25 devices.

ateh'aamaezl, 1939 p j 1,151,032, I

JOINT METHOD, or MAKING SAME John Jensen, Rockford, IlL, assignor toWhitney Metal Tool Company, Rockford, 111., a corporation of IllinoisApplication June 21, 1937, Serial No. 149,414 '1 Claims. (Cl. 29-148 Theinvention relates to joints used, for exam- Fig. 3 is an explodedperspective view illustratple, in splicing wires and the like and to amethod ing thewire ends and joint sleeve prior to the of making thesame. I assembly thereof.

I In splicing wires used as electrical conductors Figs. 4 and ;5 aretransverse sectional viewsof 5 in'telephone or telegraph systemsithasheretothe joint parts positioned in a pair of clamping .5 fore beenproposed to efiect .the splice by omdies, at the beginning and at theend respectively,

pressing atubular metal sleeve about the adjacent of the clampingoperation.

ends of the wires. Difiiculties have been encoun- For purposes ofillustration the invention hasv f .tered,' however, in thepracticalapplication of been shown and described herein as app ed 2 suchjoints. Thus, even though the sleeve be the splicing of wires but itwill be understood. that 10 clamped tightly enough to withstand thenecesthis applicationof the invention is simply exemsary' mechanicalpullingstrain when first inplary and that the appended claims areintended Stalled, the joint subsequently becomes weakened to cover allmodifications or variations within the .by corrosion resulting from theentrance of moisspirit and cope o e v nt on.

16 ture, smoke and other foreign matter into small Upon reference toFigs. 1 and 2, it-will be seen crevices between the connecter sleeveand'wires. a a Pair Of k members has been illilS This corrosion not onlyweakens the joint but trated in the iormof wires Ill and H, these wire;also materially weakens itselectrical conductivity. being splicedtogether by a ductile metal sleeve Although particular reference hasbeen had to l2 telescoped over their adjacent en P r 20 the splicing ofwires, the invention herein conand flrmly'clamped thereon. It has beenfound 20 templated is applicable to other forms of joints t at a WideVariety O metals I y be e in not only 'forwires but also for rods, bars,drawn ng jo nts o t e type herein te plated; metal tubes, pipes, and thelike, and the term that is, the rod-like'members and sleeves mayrod-like members used herein refers to all such be made of steel,copper, aluminum or other structural metals which the particularinstallag The general object of the present invention is tion requires.

to provide an improved joint and method of form- In forming'the joint inaccordance with the ing the same for rod-like members in which a presentinvention, a-tubular sleeve blank is used tubular sleeve istelescopedover a portion of'the which preferably h s a cylindri al cr ss section.30 rod-like member and compressed into such inti- 1 such as the sleeveblank I2 in Fig, 3. The in- 3 ,.mate contact with the entireperiphery'of the terior diameter of the sleeve blank is preferablytrod-like member that the joint is impervious to only slightly greaterthan the exterior diameter moisture and gases. I of the members insertedtherein, a clearance of A more specific object of the invention is. toonly about a thousandth of an inch being alprovide an improved joint andmethod of form rlowed. The ends'ol' the wires l0 and l l which 5 V lng'the same for rod-likemembers in which an are inserted in the sleeveblank l2 are arranged I initially cylindrical sleeve is compressed aboutn abutting re at on g 1) t pp oximately an inserted portion of arod-llkemember by deequal portions of the sleeve blank telescoping overformingthe sleeve into a polygonal cross-seceach of the wires. .4 tionalshape to thereby form a tight joint with Incompressing the sleeve blankI2 about the 40 the.inner walls of the sleeve in intimate contact wiresl0 and II, it is pressed or crushed in such I with the'entire peripheryof the inserted member. manner as to effect an internal flow of metalFurther objects and advantages of the invenin'the sleeve that will causeits inner wall to be tion will become apparent as the followingdedisplaced into intimate contact about the entire scription proceedsand the features of novelty peripheries 'of the inserted wires. For thispur- 45 which characterize the invention are pointed out pose, thesleeve is preferably deformed from an with particularity in the claimsannexed .to and initiallcylindrical shape into a generally polygformingapart of this specification. I onal cross-sectional shape. It'has beenfound For a better understanding oftheinventiom: that the polygon thusformed should have a 0 reference may be had to the accompanyingdrawrelatively small number of faces since if a large ing'in which I a Inumber is used; the dies act in substantially Figure 1 illustrates acompleted spliced joint the same manner as half round dies. Such halffor a'pairof wires embodying the invention. round dies give defectiveresults in that they Fig; 2 is *a transverse sectional view along thecause a slight ovaling of the sleeve transversely .55 line 2- 2 inFig.1. of the direction of movement of the dies. This present invention.

ovaling results in the formation of small'crevices; v at the apexes ofthe oval in which corrosion subsequently takes place and furthermore,the

joint is lacking in mechanical strength as compared to joints formed inaccordance with the Also, it is preferable that the final polygonalcross section of the joint have an even number of faces since theformation of the dies without undercuts is thus facilitated.,

In general, it has been found that best results are had when aninitially cylindrical blank is deformed into a hexagonal cross-sectionalshape.

' A pair of mating compression dies i4 (Figs. 4

and 5) have been illustrated for performing the shaping operations'onthe sleeve blank. ,It will be seen that these dies are provided withcomplementary recesses in their opposed faces which '1 are adapted todeform the sleeve blank into a compressiveforces are applied to thesleeve at spaced points on opposite sides of its transverse axis A-A.Then, as the movement of the dies progresses, the bottom faces I!contact the sleeve and exert pressure thereon along the transverse to orgreater than thatof the members joined.

7 I claim as my invention:

'1. Themethod pf splicing rod-like members I which comprises, insertingthe adjacent endportions oftwo cylindrical rod-like members into theopposite ends of a cylindrical metal, sleeve, and

pressing theinner wall of the sleeve into intimate I contact with thesurfaces of the rod-like members 1 about their entire peripheries by'deforming the cylindrical sleeve into' a generally polygonalcross-sectional shape.

2. The method of other'member having a generally tubular shape, andapplying pressure to the exterior of the tubularmember at a pluralityofpoints about its exterior surface to compress thesame' into "agenerally polygonal cross-sectional shapein tight t 20gripping-engagement with" the rod-like member.

3. The method of forminga frictional joint, between a portionof acylindrical rod-like member inserted within a sleeve-like member havingforming a rigid frictional telescopic joint whichcomprises, inserting apor--, tion of a cylindrical rod-likemember within an-- a cylindricalshapewhich oompriseaapplying,

pressure to the exterior of the sleeve-like'member at a plurality'ofpoints about its exterior sur-. face to compress the same into agenerally polygonal cross-sectional shape, the maximum 'width of saidpolygonal cross section being substantially equal to the initialdiameter of the sleeve-like member.

axis. As a result, the metal ,in the sleeve flows about the insertedwires l0 and l I so that an intimate contact is had about their entireperipheries. From the nature of the work pieces acted "upon it isdifllcult to determine the exact flow of metal which takesplace butapparently the initialcontact between the diesat points displacedlaterally from the transverse. axis A-A first forces the metal intocontact with the sides of the inserted wires and the subsequent contactof the bottom faces I! then forces the sleeve j into contact with theremainder. of the wire pe-' ripheries.

, sure to be exerted on the sleeve blank. Thus,

and'for aluminum, a pressure of approximately when using a, steelcore-or wire, it has been found desirable to utilize a pressure ofapproxi'-' mately eighty thousand pounds per square inch The compressionor sleeve deformation proces's described above requires a very heavypres-- twenty thousand pounds perf square inch. A

pressure tool adapted to provide the necessary high pressures throughmanual manipulation is illustrated in my ,copending application Serial5, 1938; Patent Number 2,113,087. In view of the high pressures requiredit, is desirable to compress successive portions of the sleeve blankalong its length rather than clamp the entire sleeve in a singleoperation. The length-of such,

a portion relative to the length of the sleeve is indicated by thedimension B in Fig. .l. Inaddition, the ends of. the sleeve blank arepreferably left unconfined so that any'excess metal is free 'to flow outof the ends ofthe dies longitudinally of the wires. With the arrangementdescribed,

,NO. 136,151, flledAprll 10, 1937, patented April" 4. The method offorming arigid frictional telescopic joint which comprises, inserting aportion of a cylindrical rod-like member within-a j cylindrical sleeve,and applying pressure in the -'direction,of a transverse axis'of thesleeve to the.

a smooth joint is formed substantiallyfree of side flashings. I Thejoint is'not only free from crevices or interstices'in which corrosivegases strong, having an ultimate tensile strength equal or moisture mayenter but is 'alsoextremely the inner surface opposite'sides thereof,said pressure being applied initially at points spaced laterallyfromsaid axis and subsequently along said axis to. compress the V sleeveinto tight gripping engagement with the rod'-like.member. V d l 5. Themethod of splicingrod-like members which comprises, inserting theadjacent end pot-o tions of two axially alinedgenerally cylindricalrod-like members intov the cylindrical metal sleeve opposite ends of ato'bring such adjacent ends into abutment, and applying pressure tosuccessive portions of the sleeve along its length to press the innerwall thereof into intimate con-r tact'with the surfaces of-the rod-likemembers about their entire peripheries by deforming suchsuccessiveportions of the cylindrical sleeve'into 1 a hexagonal cross-sectionalshape while leaving the ends thereof unconfined. I

, 6,. A telescopic joint forprod-like members coniover a cylindricalwith the entire periphery of the rod-like member, said'sleeve-having apolygonal cross section with the metal beneath each face of thexpolygon'l. A telescopic joint for rod-like members com-' prising, a ductilemetal sleeve member telescoped v over a cylindrical had-like member andhaving the inner surface thereof in intimate contact with theentireperiphery of the rod-like'memher, said sleeve having a hexagonalcross section with the metal beneath each face of the hexagon crushedinwardly toward said rod-like member from an initialcylindrical shape. v

. JQHNJENSEN.

55" prising, a ductile metal sleeve member telescoped rod-like memberand having thereof in intimate 'cont'act' crushed inwardly toward saidrod-like member. 1

